Evaluation of clopidogrel, hypercoagulability, and platelet count in dogs undergoing splenectomy for splenic masses.

Dogs that had splenectomy are predisposed to fatal thrombotic conditions, and thrombocytosis is a risk factor for post-splenectomy hypercoagulability. However, in veterinary medicine, there are no specific therapeutic approaches for managing this hypercoagulability. This study aimed to determine the preventive effect of clopidogrel on post-operative hypercoagulability during the first 2 weeks post-splenectomy in dogs with splenic masses. This study included 12 dogs that had splenectomy. Seven dogs received no treatment (group A), and five were treated with clopidogrel (group B). Clopidogrel was loaded at 10 mg/kg on day 2 and continued at 2 mg/kg until day 14. Blood samples were collected on the day of surgery and 2, 7, and 14 days after splenectomy in both groups. In group B, thromboelastography (TEG) was performed on the same days. In group A, there was significant elevation of platelet counts on days 7 (p = 0.007) and 14 (p = 0.001) compared to day 0. In group B, the platelet counts were significantly elevated on day 7 (p = 0.032) but no significant difference was found on day 14 compared to day 0. Platelet counts on day 14 were significantly higher in group A than in group B (p = 0.03). The lower platelet counts were correlated with alterations in TEG parameters, and no significant differences were found in the K and α-angle values at all postoperative assessment points compared to day 0. Our study suggests that clopidogrel may reduce post-operative thrombocytosis and hypercoagulability in dogs that undergo splenectomy for splenic masses.

Medical X-band linear accelerator for high-precision radiotherapy.

PURPOSE: Recently, high-precision radiotherapy systems have been developed by integrating computerized tomography or magnetic resonance imaging to enhance the precision of radiotherapy. For integration with additional imaging systems in a limited space, miniaturization and weight reduction of the linear accelerator (linac) system have become important. The aim of this work is to develop a compact medical linac based on 9.3 GHz X-band RF technology instead of the S-band RF technology typically used in the radiotherapy field. METHODS: The accelerating tube was designed by 3D finite-difference time-domain and particle-in-cell simulations because the frequency variation resulting from the structural parameters and processing errors is relatively sensitive to the operating performance of the X-band linac. Through the 3D simulation of the electric field distribution and beam dynamics process, we designed an accelerating tube to efficiently accelerate the electron beam and used a magnetron as the RF source to miniaturize the entire linac. In addition, a side-coupled structure was adopted to design a compact linac to reduce the RF power loss. To verify the performance of the linac, we developed a beam diagnostic system to analyze the electron beam characteristics and a quality assurance (QA) experimental environment including 3D lateral water phantoms to analyze the primary performance parameters (energy, dose rate, flatness, symmetry, and penumbra) The QA process was based on the standard protocols AAPM TG-51, 106, 142 and IAEA TRS-398. RESULTS: The X-band linac has high shunt impedance and electric field strength. Therefore, even though the length of the accelerating tube is 37 cm, the linac could accelerate an electron beam to more than 6 MeV and produce a beam current of more than 90 mA. The transmission ratio is measured to be approximately 30% ~ 40% when the electron gun operates in the constant emission region. The percent depth dose ratio at the measured depths of 10 and 20 cm was approximately 0.572, so we verified that the photon beam energy was matched to approximately 6 MV. The maximum dose rate was measured as 820 cGy/min when the source-to-skin distance was 80 cm. The symmetry was smaller than the QA standard and the flatness had a higher than standard value due to the flattening filter-free beam characteristics. In the case of the penumbra, it was not sufficiently steep compared to commercial equipment, but it could be compensated by improving additional devices such as multileaf collimator and jaw. CONCLUSIONS: A 9.3 GHz X-band medical linac was developed for high-precision radiotherapy. Since a more precise design and machining process are required for X-band RF technology, this linac was developed by performing a 3D simulation and ultraprecision machining. The X-band linac has a short length and a compact volume, but it can generate a validated therapeutic beam. Therefore, it has more flexibility to be coupled with imaging systems such as CT or MRI and can reduce the bore size of the gantry. In addition, the weight reduction can improve the mechanical stiffness of the unit and reduce the mechanical load.

Development of a compact X-band linear accelerator system mounted on an O-arm rotating gantry for radiation therapy.

A compact X-band linear accelerator (LINAC) system equipped with a small and lightweight magnetron was constructed to develop a high-precision image-guided radiotherapy system. The developed LINAC system was installed in an O-ring gantry where cone-beam computed tomography (CBCT) was embedded. When the O-arm gantry is rotated, an x-ray beam is stably generated, which resulted from the stable transmission of radio frequency power into the X-band LINAC system. Quality assurance (QA) tests, including mechanical and dosimetry checks, were carried out to ensure safety and operation performance according to the American Association of Physicists in Medicine's TG-51, 142, an international standard protocol established by accredited institutions. In addition, delivery QA of the radiotherapy planning system was conducted to verify intensity-modulated radiotherapy techniques. Therefore, it was demonstrated that the developed X-band LINAC system mounted on the O-arm gantry proved to be valid and reliable for potential use in CBCT image-guided radiation therapy.

A study of relationship between blood mercury concentration and hypertension in residents living in old mine fields and related factors.

BACKGROUND: In Korea, around the abandoned metal mines, heavy metals are being accumulating in the cultivated areas. Among exposed heavy metals, mercury is known to harm for cardiovascular system known to affect blood pressure. So, we studied the relationship between blood mercury level and hypertension in residents around abandoned metal mines. METHODS: From 2008 to 2011, we surveyed 7,055 residents in provinces affected by abandoned metal mines and collected data from 6 Hospitals. We conducted a personal questionnaire interview survey with residents on the basis of household questionnaires, sex, age, household income, smoking, and drinking items. Multiple logistic regression analysis was performed to investigate the association between blood mercury level and hypertension. RESULTS: We compared residents with low and high groups based on blood mercury level 5.8 µg/L, and higher group was significantly higher risk of hypertension than lower group (odds ratio [OR]: 1.277; 95% confidence interval [CI]: 1.135-1.436), also in adjusted model, higher group was significantly higher risk of hypertension than lower group (OR: 1.276; 95% CI: 1.117-1.457). CONCLUSIONS: This study showed a significant correlation between mercury and hypertension in residents around abandoned metal mines. Therefore, we should continuously monitor people who are higher than the standard value and the hypertensive patients.

Silicosis with Various Clinical Courses in a Tunnel Worker: A Case Report.

Author reports a case of 67- years- old men referred to Donga University Hospital silicosis who had worked in tunnel drilling where presumably had been exposed to high concentration free silica for almost 20 yr. This report is considered the first in Korea to the best of our knowledge since no cases on silicosis could be reported in this occupation in reviewing various literature sources in Korea. The physician's first impression was lung cancer since the CT findings. However, it turned out to be pneumonia and silicosis. It was eventually diagnosed with silicosis and pneumonia, and tuberculosis. The patient is suffering from various clinical courses for long time.

A case of complicated silicosis with a complex clinical course in a glass manufacturing worker.

We reported a case of complicated silicosis that occurred in a glass manufacturing plant worker who had presumably been exposed to low-concentration free silica for almost 20 years. To the best of our knowledge this report is the first in the Republic of Korea. The physician's first impression was cancer since the enlargement of neck and supraclavicuar lymph nodes had clearly progressed and metastasis was suspected in ultrasonography. However, it turned out to be reactive hyperplasia and anthracosis. Although lung cancer was suspected and tests were performed in 2 hospitals due to repetitive cough and dyspnea, along with weight loss of approximately 10% over the course of 7 months, the patient was eventually diagnosed with complicated silicosis and pneumothorax occurred after 1 year. Herein, we report this case with a literature review.

Cementless total hip arthroplasty for patients with Crowe type III or IV developmental dysplasia of the hip: two-stage total hip arthroplasty following skeletal traction after soft tissue release for irreducible hips.

BACKGROUND: Total hip arthroplasty (THA) for severe developmental dysplasia of the hip (DDH) is a technically demanding procedure for arthroplasty surgeons, and it is often difficult to reduce the hip joint without soft tissue release due to severe flexion contracture. We performed two-stage THAs in irreducible hips with expected lengthening of the affected limb after THA of over 2.5 cm or with flexion contractures of greater than 30 degrees in order to place the acetabular cup in the true acetabulum and to prevent neurologic deficits associated with acute elongation of the limb. The purpose of this study is to evaluate the outcomes of cementless THA in patients with severe DDH with a special focus on the results of two-stage THA. METHODS: Retrospective clinical and radiological evaluations were done on 17 patients with Crowe type III or IV developmental DDH treated by THA. There were 14 women and 3 men with a mean age of 52.3 years. Follow-ups averaged 52 months. Six cases were treated with two-stage THA followed by surgical hip liberalization and skeletal traction for 2 weeks. RESULTS: The mean Harris hip score improved from 40.9 to 89.1, and mean leg length discrepancy (LLD) in 13 unilateral cases was reduced from 2.95 to 0.8 cm. In the patients who underwent two-stage surgery, no nerve palsy was observed, and the single one-stage patient with incomplete peroneal nerve palsy recovered fully 4 weeks postoperatively. CONCLUSIONS: The short-term clinical and radiographic outcomes of primary cementless THA for patients with Crowe type III or IV DDH were encouraging. Two-stage THA followed by skeletal traction after soft tissue release could provide alternative solutions to the minimization of limb shortenings or LLD without neurologic deficits in highly selected patients.

Malignant fibrous histiocytoma of the maxillary sinus in a spray painter from an automobile repair shop.

BACKGROUND: We report a case of a spray painter who developed malignant fibrous histiocytoma (MFH) of the maxillary sinus following long-term exposure to chromium, nickel, and formaldehyde, implying that these agents are probable causal agents of MFH. CASE REPORT: The patient developed right-sided prosopalgia that began twenty months ago. The symptom persisted despite medical treatment. After two months, he was diagnosed with MFH through imaging studies, surgery, and pathological microscopic findings at a university hospital in Seoul. His social, medical, and family history was unremarkable.The patient had worked for about 18 years at an automobile repair shop as a spray painter. During this period, he had been exposed to various occupational agents, such as hexavalent chromium, nickel, and formaldehyde, without appropriate personal protective equipment. He painted 6 days a week and worked for about 8 hours a day.Investigation of the patient's work environment detected hexavalent chromium, chromate, nickel, and formaldehyde. CONCLUSIONS: The study revealed that the patient had been exposed to hexavalent chromium, formaldehyde, and nickel compounds through sanding and spray painting. The association between paranasal cancer and exposure to the aforementioned occupational human carcinogens has been established. We suggest, in this case, the possibility that the paint spraying acted as a causal agent for paranasal cancer.

Cause of infection in proximal tibial endoprosthetic reconstructions.

INTRODUCTION: The underlying cause of proximal tibial prosthetic failure by infection is unclear. We asked: (1) Is resection amount related to prosthetic infection? (2) What other risk factors are related with infection? (3) What are the survivorship and functional outcomes of proximal tibial endoprosthetic reconstruction? METHODS: Sixty-two patients who underwent modular proximal tibial megaprosthesis reconstruction were analyzed. Follow-up duration averaged 98 months (range 26-240 months). Associations between prognostic variables and prosthesis survival were assessed. RESULTS: The 10-year prosthetic survival of the 62 implants was 73.9 ± 11.7%. Prostheses were removed in 16 (25.8%) patients for infection and 3 of the 16 underwent amputation. Resection of >37% (P = 0.016) of the tibia was found to be related to infection. Application of chemotherapy (P = 0.912) and use of synthetic material to fix the patella tendon (P = 0.2) were not found to influence prosthetic survival. Functional outcomes (determined by the MSTS system) of the 52 patients that maintained a mobile joint averaged 24.2 (81%) (range 18-28). CONCLUSIONS: Our study suggests that the amount of bone resection is related with prosthetic failure by infection, however, the contribution of other risk factors should not be underestimated.

Antioxidant effects of fermented sea tangle (Laminaria japonica) by Lactobacillus brevis BJ20 in individuals with high level of γ-GT: A randomized, double-blind, and placebo-controlled clinical study.

A randomized, double-blind, and placebo-controlled clinical study was performed to evaluate the antioxidant effects of fermented sea tangle (FST) on healthy volunteers with high levels of γ-glutamyltransferse (γ-GT). Forty-eight participants were divided into a placebo group and an FST group that received FST (1.5 g/day) for 4 weeks. Serum γ-GT, malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities were determined before and after the trial. Administering FST significantly decreased serum levels of γ-GT and MDA. Additionally, SOD and CAT activities were significantly augmented compared to those in the placebo group after 4 weeks, but no significant alteration was observed in GPx activity compared to that in the placebo group. Our findings indicate that FST enhanced the antioxidant defense system in a healthy population and may be useful as a functional food ingredient.

Occupational lung cancer surveillance in South Korea, 2006-2009.

OBJECTIVES: The lung cancer mortality in Korea has increased remarkably during the last 20 years, and has been the first leading cause of cancer-related deaths since 2000. The aim of the current study was to examine the time trends of occupational lung cancer and carcinogens exposure during the period 2006-2009 in South Korea, by assessing the proportion of occupational burden. METHODS: We defined occupational lung cancer for surveillance, and developed a reporting protocol and reporting website for the surveillance of occupational lung cancer. The study patients were chosen from 9 participating university hospitals in the following 7 areas: Seoul, Incheon, Wonju, Daejeon, Daegu, Busan, and Gwangju. RESULTS: The combined proportion of definite and probable occupational lung cancer among all lung cancers investigated in this study was 10.0%, 8.6%, 10.7%, and 15.8% in the years 2006 to 2009, respectively, with an average of 11.7% over the four-year study period. The main carcinogens were asbestos, crystalline silica, radon, polyaromatic hydrocarbons (PAHs), diesel exhaust particles, chromium, and nickel. CONCLUSION: We estimated that about 11.7% of the incident lung cancer was preventable. This reveals the potential to considerably reduce lung cancer by intervention in occupational fields.

Sexual activity and hepatitis B and C virus infection among young adults after introduction of a vaccination program in an area of high endemicity.

BACKGROUND: In areas where hepatitis is endemic, little is known about the sexual transmission of HBV after introduction of an HBV vaccination program. METHODS: We used a self-administered questionnaire and serological tests for HBsAg, anti-HBs, anti-HBc, and anti-HCV to examine the role of sexual activity, as well as sociodemographic status, lifestyle habits, and a history of vaccinations, transfusions, and surgery, in the transmission of HBV and HCV in Korea. The subjects were 865 female and 541 male university students (median age, 19 years; age range, 16-25). RESULTS: Overall seropositivity was 8.1% for HBsAg, 69.3% for anti-HBs, 21.3% for anti-HBc, and 0.4% for anti-HCV. Regarding HBV, 8% of the subjects were chronic carriers or had recently been infected, 22.8% were never exposed and nonvaccinated, 16.6% were exposed noncarriers, and 52.7% had most likely been vaccinated. We found a significant association between HBsAg seropositivity and history of sexual intercourse (Odds Ratio, 1.8; 95% CI, 1.1-2.8). Students without serologic evidence of immunization against HBV were more likely to have become HBsAg-positive after becoming sexually active. CONCLUSIONS: Our findings suggest that sexual transmission does occur among adolescents and young adults who have not been vaccinated, whereas vaccination protects individuals from becoming an HBV carrier after becoming sexually active.

Female-to-male proportions of the head and face in Koreans.

It is well known that the head and face are smaller in female subjects than in male subjects. However, almost all previous studies have quantified the size difference between female and male subjects as simple numerical values, which might not clarify the difference. The present study evaluated the female-to-male proportions of the head and face so as to clarify the sex-related differences. A total of 1939 female subjects and 1398 male subjects were divided into 3 age groups: young (20-39 y), middle-aged (40-59 y), and elderly (60-79 y). The dimensions were classified into 3 categories: 5 cephalic, 3 frontal facial, and 6 lateral facial. The female-to-male proportions of individual dimensions were compared in the 3 age groups using the following formula: female measurement value x 100/(mean of male measurement value). The female-to-male proportions of the cephalic dimension increased with age, with the female cephalic dimensions overall being about 96% of the male cephalic dimensions. The female-to-male proportions of the frontal facial dimension were constant across the age groups, with the female frontal facial dimensions overall being 95% of the male frontal facial dimensions. The female lateral facial dimension increased markedly from the young to middle-aged group and was constant or decreased slightly from the middle-aged to the elderly group. Overall, the female lateral facial dimensions were approximately 97% of the male lateral facial dimensions. The present study will suggest a new approach to elucidate those sex-related dimensional differences that are characteristic of female and male subjects.

Oncostatin M promotes osteogenesis and suppresses adipogenic differentiation of human adipose tissue-derived mesenchymal stem cells.

Oncostatin M (OSM) is a multifunctional cytokine of the interleukin-6 family and has been implicated in embryonic development, differentiation, inflammation, and regeneration of liver and bone. In the present study, we demonstrated that treatment of human adipose mesenchymal stem cells (hADSCs) with OSM-attenuated adipogenic differentiation, as indicated by decreased accumulation of intracellular lipid droplets and down-regulated expression of adipocytic markers, such as lipoprotein lipase and PPARgamma. However, OSM treatment stimulated osteogenic differentiation, as demonstrated by the increase in matrix mineralization and expression levels of osteogenic differentiation markers, including alkaline phosphatase, Runx2, and osteocalcin. OSM treatment induced activation of JAK2, JAK3, and ERK in hADSCs, and pre-treatment of hADSCs with the JAK2 inhibitor, AG490, significantly restored the OSM-induced inhibition of adipogenic differentiation. Whereas, the JAK3 inhibitor, WHI-P131, and the MEK inhibitor, U0126, had no effects on the anti-adipogenic activity of OSM. On the other hand, the pro-osteogenic activity of OSM was prevented by treatment of the cells with WHI-P131 or U0126, but not with AG490. These results indicate that distinct signaling pathways, including JAK2, JAK3, and MEK-ERK, play specific roles in the OSM-induced anti-adipogenic and pro-osteogenic differentiation of hADSCs.

[Epidemiologic study of Clonorchis sinensis infestation in a rural area of Kyongsangnam-do, South Korea].

OBJECTIVES: To investigate the prevalence of Clonorchis sinensis infestation and to determine the associated risk factors among a population in a part of the rural area of Gyeongsangnam-do, Korea, which is an area known to have a high mortality from liver cancer and a high infection of C. sinensis. METHODS: The study population consisted of those people who have lived in rural areas and who were over 40 years old. This study was performed in 5 areas during the period from 1999 to 2003. Informed consents were obtained from the 2,381 study participants, and these people were interviewed about their life style habits with using the structured questionnaire that was administered by trained staff members. The subjects underwent blood sampling and their stool specimens were examined by using the Formalin-ether sedimentation technique. RESULTS: Among the study subjects (N=2,381), the positivity for C. sinensis in the stool was 34.4% (95% CI= 36.3-42.5); it was 39.4% (95% CI=36.3-42.5) in the males and 30.9% (95% CI=28.5-33.3) in the females. The positivity for C. sinensis was associated with current alcohol drinking (odds ratio=1.8, 95% CI: 1.5-2.1) and raw fish consumption (odds ratio 1.2, 95% CI: 0.9-1.6). CONCLUSION: The present study confirmed the high prevalence of C. sinensis in the study subjects. It is necessary to establish consistent medical management and education programs for the treatment and prevention of C. sinensis infestation in the rural inhabitants of Korea.

[Two cases of histopathologically advanced (stage IV) early gastric cancer].

Various minimally invasive surgical techniques in some cases of early gastric cancer are becoming common practice. However, there are rare cases of advanced cancer with distant metastasis although the invasion of the gastric wall is limited to the mucosa and/or submucosa (defined as early gastric cancer according to UICC-TNM classification). We report two cases of early gastric cancer with distant metastasis (stage IV). Both tumors were defined as early cancer because they were confined to the submucosa. One was a type IIa early cancer, histologically classifiable as a signet ring cell carcinoma (according to the Japanese Classification of Gastric Carcinoma and UICC-TNM classification); the other was a surface spreading type IIb + IIc, classifiable as a signet ring cell carcinoma, too. Stage IV factors were ovarian metastasis (Krukenberg tumor) in the former and N3 in the latter case.

Prevalence and determinants of genital infection with papillomavirus, in female and male university students in Busan, South Korea.

BACKGROUND: Little is known about the prevalence of human papillomavirus (HPV) infection in young adults in Asia. METHODS: We invited female and male students in Busan, South Korea, to participate in a survey that included, for females, self-collection of vaginal cells and, for males, physician-performed collection of exfoliated genital cells. The prevalences of 25 HPV types were evaluated, by a polymerase chain reaction-based assay, in 672 female students (median age, 19 years) and in 381 male students (median age, 22 years). RESULTS: HPV DNA was detected more frequently in female students (15.2%) than in male students (8.7%); in both sexes, high-risk HPV types were predominant. Among sexually active students, HPV prevalence was 38.8% in females and 10.6% in males. In female students, currently smoking cigarettes and having multiple lifetime sex partners were the strongest risk factors for HPV infection; in male students, associations between HPV prevalence and sexual habits were similar to those in female students but never attained statistical significance. CONCLUSIONS: Young women in South Korea start having penetrative sexual intercourse relatively late (median age, 18 years), but, once they begin, HPV prevalence quickly rises to levels comparable with those found in university students in the United States and in northern Europe. The high rate of participation in our study suggests that trials of new vaccines against HPV may be feasible among university students in South Korea.

A seroepidemiological Study of Hepatitis B and C Virus (HBV and HCV) Infections in the Young Population in parts of Busan, Korea.

OBJECTIVES: To investigate the prevalence of hepatitis B and C virus infections and determine the associated risk factors among young adults in Busan, Korea, which is known to have a high incidence of liver cancer. METHODS: The study population consisted of volunteer participants in a health survey during 2002, which included 1, 350 students (515 males and 835 females) aged between 16 and 24 years, from three different schools in Busan. The participating students were asked to fill in a selfadministered questionnaire which included lifestyle habits and risk factors of hepatitis. Sera obtained from the participants were studied for HBsAg, anti-HBs, and Anti- HCV by enzyme immunoassay (EIA) method and for liver function tests. RESULTS: Among the study subjects (N=1, 350), the seropositivities of HBsAg 7.9% (95% CI=7.8-8.0), 7.6% (95% CI=7.6-7.7) in male and 8.1% (95% CI=8.0-8.2) in female. And the seropositivity of Anti-HBs was 69.7% (95% CI=69.0- 70.4), 70.5% (95% CI=69.8-71.2) in male and 69.2% (95% CI=68.5-69.9) in female. The seropositivity of Anti-HCV was 0.4%, 0.2% in male and 0.5% in female. The seropositivity for HBsAg in the subjects not having a hepatitis B vaccination history was twice (95% CI=1.0-4.4) that of those that did. Also, the seropositivity for HBsAg in subjects having experienced sexual intercourse was 1.7 times (95% CI=0.9-3.0) that of the subjects who had not. CONCLUSIONS: The present study confirmed the high prevalence of HBsAg seropositivity and sexual transmission of HBV among adolescents and young adults may occur. Further studies to evaluate the relationship between HBV vaccination and sexual transmission are required for the young population in Korea.